Get this from a library! Freeboard allowances for waves in inland reservoirs. [ Thorndike Saville; Elmo W McClendon; Albert L Cochran]. Derive simple wave prediction methods for British inland reservoirs taking account of E W, & Cochran A L, () Freeboard allowances for waves in Inland. overtopping due to wind-generated waves and reservoir setup. • Relationships in “Freeboard Allowances for Waves in Inland Reservoirs.

Freeboard Allowances for Wave in Inland Reservoirs

A model of the phenomenon caused by wind. Characteristics of wave spectrum. Our article is interested in water rise reservois to wind set-up and wave run-up with respect to the crest of the dam. The maximum elevation of the water level at the neighborhood of the upstream face is defined by the following formula:. The notion of effective fetch has been introduced to take into account the following fo. For the continuity of our calculations we would suppose that the waves have had enough time to attain their maximum height and that the condition of the wave height supported is always verified for periods of wind superior to one hour.

The fetch represents the distance which separates the dam from the shore where the wind is blowing. We consequently conclude that the crest of the structure is sufficiently high to resist any risk resulting from repeated run-up of waves on the crest.

Distance to the dam – reservoir and the calculation of the effective fetch. The calculation of minimum freeboard for the embankment dam. For each of the configurations considered, the criteria for expected minimum freeboard in table 1 are respected for all the dams considered. An average depth of 30m has been retained in the ensuing calculations. The impact height of a wave is a combination of an upsurge in water level and run-up height R associated to a wave height H in deep water.

Many configurations are considered in the presentation of our calculations [ 1 ]. These latter considerations will take into account the following different parameters.

Freeboard Allowances for Waves in Inland Reservoirs

The freeboard f is defined as the difference between the height of the dam crest and the maximum elevation attained by the waves on the upstream face of the dam.

H is defined as the average height of waves over the percentage of the highest waves. When the waves hit the upstream face of the dam, we assist in an upsurge of the water level due to the fact that the kinetic energy in the waves is transformed into potential energy.

This length is called the effective freboard and denoted Fe. Historically, we usually work with the significant height. The development objective of the Lom Pangar Hydropower Project for Cameroon is to increase hydropower generation capacity and reduce seasonal variability of water flow in the Sanaga River and to increase access to electricity [ 78 ]. Journal of Engineering and Technology.

Determining the wave run-up height. We would however carry out a study on the sensitivity of the speed of wind. Measures carried out in the sea and in the reservoir during tempests have shown that the characteristics of the wave spectrum are as follows:.

The method used here to determine the effective fetch is based on recommendations from USACE [ 56 ]. This increase in the height of the waves is called wave run-up. Table 4 and 5 synthesize the results obtained for the laterite backfill embankment as well as the transition rock fill embankment.

The latter is defined as the sum of the wind set-up S and the wave run-up R for a given wave height H. Laterite Embankment alllowances at 3.

Freeboard Allowances for Waves in Inland Reservoirs

The value of the rise in water level is calculated by applying the Zuider Zee formula Fell et al. When a wave meets a vertical face, the part of the energy transported by the former is dissipated in the form of turbulence whereas the remaining energy is transformed into potential energy thus causing an upsurge in the water level due to wave run-up.

The waves generated by the wind under the hypothesis of great depth do not have the same height. When Z reservoiris The RCC dam — Calculation of freeboard.